Crane for mailbags



. Dec. 2, 1941. D. w.- STANLEY CRANE FOR MAILBAGS Filed April 10, 1939 Patented Dec. 2, 1941 UNITED STATES PATENT OFFICE 4 Claims.

. This invention relates to. railway mail bag handling devices and more particularly to cranes for supporting a mail bag adjacent to a railroadtrack in a manner whereby a hook disposed outwardly at a side of a moving railway mail car gathers a bag supported by the crane for transferring the bag into the. car.

It is an object of the invention to provide means carriedv by said crane for applying a stretching stress to the bag while the latter is supported by the crane.

Other and further objects and advantages of the invention will be understood from the following detailed description thereof.

In the drawing:

Figure 1 is a side elevation of a collapsible mail crane embodying the present invention.

Figure 2 is a longitudinal section of a tele.- scopic brace arm employed.y

Figure 3 is a transverse section takenA on line 3-3 of Figure 1.

Figure 4 is a plan view of a fragment of a railway mail car provided with a mail bag hook.

The provision and use4 of a conventional crane is well known together with th'e operation thereof and. is believed to need no particular description herein. streamlined trains` and resultant from the high speeds attained in the operation thereof .such trains generate a suction suflicient, in numerous. instances, to release mail bags from supporting cranes before the hooks carried by the mail cars of such trains engage with the bags whereby the primary railroads have from one to five mail bag pick up failures each day causing delay inforwarding mail, and in several known instances, bags have fallen upon the tracks, becoming sheared by the wheels of a train, the mail lost and destroyed or scattered by the suction of the train for several miles along. the road, resulting in iines imposed on railroads in accordance with their mail transportation contracts as well as discommoding the public in the delivery of mail, and the present invention contemplates the provision of means for obviating such practice and lessening the number of mail bag pick up failures.

In the drawing I indicates generally a collapsible mail crane h'aving a post II which, in use, is vertically disposed. The lower end I2 of the post is provided with a foot, not shown, for

supporting it adjacent a railway track in a well known manner. Steps, not shown, are conventionally provided adjacent said post for facilitating the operation of attaching a mail bag to the crane.

Since the advent of the modern The upper end I3 of the. post is provided with a horizontally disposed bracket-arm I4 having a sleeve or the like I5 for purposes. later described. The outer end of the bracket-arm is usually bi'- fu-rcated for receiving between the forks thereof an upper arm I6 which' is pivotally attached as at I'I to the bracket-arm` for swinging movement in a vertical direction. The swingable arm I.6 in use is disposed at an approximate right-angle with respect. to a railroad track..

A rod I8 which in use is disposed vertically or inl approximate parallelism with respect, to the post I3 isv adapted to have vertical sliding movements through the sleeve I5 of the guide-bracket arm I4.

A brace, generally indicated at I9, is employed for supporting the arm I6 in an approximate horizontal position at times when the rod I8 is supported in a stationary position, as shown in Figure 1, and as later described. One end of'the brace ispivotally attached' as at 20 to the arm I6 between the. ends of the latter and the other end of the brace I9 is similarly pivotally attached to the rod I8 asy at 2| and, as shown in Figure 1.

Between the. upper and lower ends of the post Il a second. bracket-arm 22 is rigidly clamped or otherwisev suitably secured to the postv II. The distance provided between said bracket-arms is greater than the longitudinal length of a standard size mail bag, said brackets I4 and 22 being disposed in vertical alignment with respect to each' other.

A lower arm 23 is pivotally attached as at 24 to the lower-bracket 22 and is adapted to swing in a vertical direction.

The lower bracket 22 is bifurcated and the pivoted end of the arm 23 is arranged with respect thereto, as shown in Figure 3. A suitable detent 25 is secured to and extends across the forks of the lower bracket 22, said lower arm being arranged to abut the detent 25 during upward swinging movements thereof. The detent 25 prevents an undue upward movement of the arm 23. During mail bag pick-up operations the arm 23 is disposed in an approximate horizontal position,

as shown in Figure 1 and in approximate vertical alignment with respect to the upper arm I6.

The free outer ends of the arms I6 and 23 are eachA provided, respectively, with `hooks 26 and 27, said hooks being formed integral with and disposed at the outer ends of coiled springs 28. The inner ends 29 of said springs are secured to their respective arms by any suitable means such as extending said inner ends into said arms,

so the looped portions of the hooks 26 and 21 being disposed in directions reverse with respect to each other, as shown in Figure 1. The hooks 2G and 21 in conjunction with the said coiled springs provide releasable means for engaging the rings of the mail bag 3|.

The mail bag 3| is of standard type, the bags of the latter being approximately of uniform longitudinal length. As is well known in use the lengths of said bags vary in accordance with the quantity of mail contained within each, since said bags are made of exible canvass. It is also well known that a heavily laden bag is of shorter length than a bag containing comparatively few pieces of mail matter whereby the coil springs 28 do not compensate suiiciently for variations in the lengths and weights of laden bags, Sunicient to hold the rings 3U of said bags attached to the hooks 25 and 21 during movement of the engine of a streamlined train past a bag on account of the suction generated by the engine during high speed travel, said bags becoming often sucked from said hooks before the rst mail car of the train reaches the crane I il.

Referring to Figure 4, 32 indicates the oor of a railway mail car and 33 the doorway opening disposed at the side thereof, said opening being provided with a vertically disposed wall 34 to which is secured a pivot bolt or the like 35 for a mail bag pick-up hook 36, the latter having a handle 31. When not in use the hook 35 and handle 31 are vertically disposed within the doorway opening 33 in a well known manner and in use the operator while standing on the floor 32 holds the handle 31 horizontally for causing the hook 35 to be correspondingly disposed outwardly of the side of the car and in alignment with the bag 3| for engaging with said bag in a manner well known.

The foregoing described parts, with the exception of the telescopic feature of the brace I9, are well known to the art and the improvement consists of providing means for attenuating the bag 3Irwhile it is suspended between the hooks 26 and 21, said means being such that the bag becomes stretched at times when it contains but few pieces of mail matter and to such an extent that the rings 3E) of the bag will remain gripped and held by their respective hooks against the urge of the suction generated by said high speed trains. Y

Heretofore the brace I9 has been of solid construction and utilized solely to support the arm I6 horizontally at times when the lower end of the rod I8 rests upon and is supported by the lower arm 23, as in use and as later described herein. The springs of the hooks 26 and 21 have always been inadequate to stretch mail bags, said hooks and springs not having been so constructed that a stretching function could be adequately derived therefrom, whereby lightly laden bags were merely suspended from the upper hook 28 and in a manner such that often the lower end of a bag would swing away from the lower hook on windy days before thearrival of a train, necessitating tying the lower ring of a bag to the lower hook with string.

Referring now to the said improvement and to the particular specific preferred embodiment thereof shown in Figure 2 said improvement preferably includes an outer pipe section 33 and a pipe section 39 having an end siidably disposed within the section 38. The section 33 is provided with oppositely disposed elongated slots 43 through which a detent pin 4I extends, said pin also extending through opposite sides of the pipe 38 whereby telescopic, longitudinal, sliding movements of the member 38 with respect to the member 39 are permitted and said pin 4I prevents a complete detachment of said members with respect to each other.

A second pin or abutment 42 extends through the member 38 approximately mid-way between the ends of the latter. A coil spring 43 is positioned between the pin 42 and the inner end of the member 39 for normally urging the opposite ends of the device I9 away from each other.

The outer ends of the members 38 and 39 are provided with like clips 45 each having a transversely disposed aperture 46 for the reception therethrough of the pivot pins 20 and 2|, shown in Figure 1. The clips 45 are conventional to the thousands of mail cranes in use at present, whereby in order to install the device of the present invention said clips 45 are interchangeable with the like clips now in use. The clips 45 are provided with-sockets for receiving ends of the new device and any suitable means such as the rivets 41 are employed for locking the clips to the ends of said device.

In the operation of mail cranes of collapsible type, such as shown in Figure 1, it will be understood that the arms IS and-23 together with the rod I8 are normally in the down position shown by the dotted lines in Figure 1. In order to attach the bag 3| for pick up purposes the operator ascends the heretofore mentioned steps with the bag in one hand and attaches the upper end of the bag to the hook 26, moving the rod I8 to an upwardly disposed position and at this time he may rest the lower end 48 of the rod I8 upon the lower bracket-arm 22 whereby the bag 3| is suspended in a vertical position. rl`he lower arm 23 is next swung to a horizontal position and by pulling downwardly upon the lower ring 30 of the bag 3| and against the urge of the coil spring 43 of the new device, the operator is thereby enabled to attach the lower ring 3B of the mail bag to the hook 21; whereupon the device is in an operative position, although the conventional practice is to then position the lower end 48 of the rod I8 upon the arm 23 and closely adjacent to the pivot pin 24 for said lower arm, as shown in Figure 3, whereby at the time the bag is released gravity actuates the rod IB to drop downwardly, permitting the arm I6 to collapse at the time the lower arm 23 is permitted to move away from a supporting position with respect to the rod I8.

As thus described it will be understood that since the arm 23 is prevented from swinging above a horizontal position by the detent 25 that the mail bag 3| prior to the pick up thereof becomes stretched, resultant from the spring 43 urging the outer end of the arm I6 upwardly away from the arm 23, whereby the bag 3| is releasably held between the arms more securely than heretofore and the bag 3| is prevented from detachment from the hooks 26 and 21 by means of train suctionLhigh wind velocities from any source or the y like and that inequalities in the lengths of laden mail bags are correspondingly compensated for.

From the foregoing description it is thought to be obvious that a crane for mail bags equipped in accordance with my invention is particularly well adapted for use by reason of the convenience and facility with which it may be assembled and operated, and it will be also obvious that my invention is susceptible of some change and modiiication without departing from the principles and spirit thereof and for this reason I do not wish it to be understood as limiting myself to the precise arrangement and formation of the several parts herein shown in carrying out my invention in practice except as claimed.

I claim:

1. A collapsible mail crane comprising a vertically disposed post, a vertically slidable rod, a bracket-guide for said rod secured to said post adjacent the top of the latter, an upper arm pivotally connected to said bracket for swinging movements in a vertical direction, a lower arm pivotally connected to said post between the lower end of the latter and said bracket, said lower arm being adapted to swing from a normal vertical position to an approximate horizontal position, releasable means disposed at the free end of each of said arms for `attaching a mail bag therebetween, a detent for preventing the free end of said lower arm from swinging above an approximate horizontal position, an extension member having an end pivotally connected to and between the ends of said upper arm, a tubular member having an end pivotally connected to said rod, the lower end of said rod being adapted to rest upon said lower arm adjacent the pivotal connection thereof, the opposed end of said extension member telescoping into said tubula-r member, a stop in said tubular member, and a spring disposed between said stop and said opposed end of the extension member for urging said members away from each other to tension said bag.

2. A collapsible mail crane 4comprising a vertically disposed post, a vertically disposed rod, an upper arm pivotally connected to said post, a lower arm mounted on said post for only downward movement away from said upper arm, releasable means disposed at the free end of each of said arms for attaching a mail bag therebetween, an extension member having one end connected to said upper arm, a tubular member con- Qetd t Sad TOQ- ani. @eleSCOPing We? Sad 6X- tension member, a stop in said tubular member, and a spring disposed between said stop and the other end of said extension member for urging said arms away from each other for attenuating said bag.

3. A collapsible mail crane comprising a vertically disposed support, an upper arm pivotally connected to said support, a lower arm mounted on said support for only downward movement away from said upper arm, releasable means disposed in the free end of each of said arms for attaching a mail bag therebetween, an extension member having one end connected to said upper.

arm, a second member connected to said support and telescoping over said extension member, a seat in said second member, and a spring disposed between said seat and the other end of said extension member for urging said upper arm away from said lower arm for attenuating the bag.

4. In a crane for supporting a railway mail bag adjacent a railroad track, -a supporting standard, two arms mounted on said standard in spaced apart relation and extending laterally therefrom, one of said `arms being pivotally mounted relative to said standard, the other of said arms mounted only for movement away from said first arm, releasable means carried by said arms for attaching said bag therebetween, and means for urging the releasable means of said upper arm away from said lower arm, said means comprising two elongated members disposed in slidable relation to each other, means for maintaining said disposition of said members, one of said members vhaving an end connected to said upper arm, the other of said members having an end connected to said standard, and resilient means for urging the opposite end of said rst-mentioned member away from the second-mentioned member for tensioning the bag.

DALLAS W. STANLEY. 

